我为CBUID设置了以下类别：

@interface CBUUID (StringExtraction)

- (NSString *)representativeString;

@end

@implementation CBUUID (StringExtraction)

- (NSString *)representativeString;
{
    NSData *data = [self data];

    NSUInteger bytesToConvert = [data length];
    const unsigned char *uuidBytes = [data bytes];
    NSMutableString *outputString = [NSMutableString stringWithCapacity:16];

    for (NSUInteger currentByteIndex = 0; currentByteIndex < bytesToConvert; currentByteIndex++)
    {
        switch (currentByteIndex)
        {
            case 3:
            case 5:
            case 7:
            case 9:[outputString appendFormat:@"%02x-", uuidBytes[currentByteIndex]]; break;
            default:[outputString appendFormat:@"%02x", uuidBytes[currentByteIndex]];
        }

    }

    return outputString;
}

@end

对于此输入：

NSLog(@"UUID string: %@", [[CBUUID UUIDWithString:@"0bd51666-e7cb-469b-8e4d-2742f1ba77cc"] representativeString]);
NSLog(@"UUID string2: %@", [[CBUUID UUIDWithString:@"1800"] representativeString]);

它产生以下输出：

UUID string: 0bd51666-e7cb-469b-8e4d-2742f1ba77cc
UUID string2: 1800

并为16字节UUID保留适当的断字，同时支持简单的2字节UUID。

对于所有说CBUUID是通过CFUUIDRef免费桥接的人来说，事实并非如此。

CBUUID * foo = [CBUUID UUIDWithString:CBUUIDCharacteristicExtendedPropertiesString];
CFStringRef fooBar = CFUUIDCreateString(NULL, (__bridge CFUUIDRef)foo);
if (![CBUUIDCharacteristicExtendedPropertiesString isEqualToString:(__bridge NSString *)fooBar])
    NSLog(@"fubar!");

它没有坠毁，但你把垃圾弄出来了。它可能是唯一识别垃圾的，但它不可能是往返。
PS：这并没有作为注解工作，因为奇怪的是，注解不允许代码格式化。

iOS 7.1（昨天发布，11/18/13）在CBUUID上引入了以下属性：
@property(nonatomic, readonly) NSString *UUIDString

• UUID表示为字符串。（只读）*

从CBUID类引用。
同样值得注意的是，对于将UUID字符串与CBUUID进行比较，这是可行的：

if ([cbuuidInQuestion isEqual:[CBUUID UUIDWithString:@"1234-5678-9012-1234"]]) {
    // isEqual tests for "the same UUID"
    // == tests for "the same CBUUID object"
}

我知道已经有7个月没问过了，但是... CBUUID是“免费桥接”到CFUUID，最简单的转换方法是

//CBUUID* uuid = descr.UUID;
 NSString* str = CFUUIDCreateString(nil, uuid);

以下是布拉德Larson的回答：

import CoreBluetooth

extension CBUUID {

    func representativeString() -> String {
        let data = self.data

        let bytesToConvert = data.length
        let uuidBytes = UnsafePointer<CUnsignedChar>(data.bytes)
        var outputString = String()

        for currentByteIndex in 0..<bytesToConvert {
            switch currentByteIndex {
            case 3,5,7,9:
                outputString += String(format: "%02x-",uuidBytes[currentByteIndex])
            default:
                outputString += String(format: "%02x",uuidBytes[currentByteIndex])
            }
        }

        return outputString
    }
}

从iOS 7.1 UUIDString属性是存在的，但对于特定的iOS7，上述扩展是很好的选择。

Objective C和Swift都有原生方法，而且是非常直接的方法。

NSString *str = characteristic.UUID.UUIDstring;

Swift语言的链接到库-> https://developer.apple.com/documentation/corebluetooth/cbuuid/1518742-uuidstring?language=objc

Swift使CBUID示例的uuidString属性变得容易。

let x = "B5E4B1AA-A851-4148-BF91-03B9B342295C"
let x_uuid = CBUUID(string: x)        
print(x_uuid.uuidString)

https://developer.apple.com/documentation/corebluetooth/cbuuid/1518742-uuidstring

布拉德的answer完成了它的工作，但是使用NSUUID类的解决方案可以更简单（尽管可能不会更高效）：

// CBUUID+ToString.h

#import <CoreBluetooth/CoreBluetooth.h>

@interface CBUUID (ToString)

- (NSString *)toString;

@end

// CBUUID+ToString.m

#import "CBUUID+ToString.h"

@implementation CBUUID (ToString)

- (NSString *)toString {
    if ([self respondsToSelector:@selector(UUIDString)]) {
        return [self UUIDString]; // Available since iOS 7.1
    } else {
        return [[[NSUUID alloc] initWithUUIDBytes:[[self data] bytes]] UUIDString]; // iOS 6.0+
    }
}

@end

以下是我工作没有任何错误：

NSString *str = [[NSString alloc] initWithFormat:@"%@",  CFUUIDCreateString(nil, peripheral.UUID) ];